For the alkaline phenolic system, a special inhibitor
must be pre-mixed with the sand to prevent the alkaline salts from causing low temperature fusing of sand grains. Termal reclamation with the addition of pre- and
post-mechanical scrubbing also can be used for reclaiming Green Sand back to the core shop.
Sand Cooling and Classification Often overlooked, the sand cooler/classifier is equally as
important as the attrition unit because unless all of the dust and fine particles from the sand are removed, there will not be a reduction in the loss on ignition (LOI) at the mixer. Typically a cooler/classifier would be a fluidized bed
type with a copper tube heat exchanger for sand cooling. Te fluidizing air and the extracted air must be finely bal- anced to provide a negative pressure inside the fluidizing chamber. Tis pressure can be adjusted according to the amount of fines in the sand. Fluidized sand is not abrasive, so copper tubes can be
employed as the heat transfer medium. Using copper, the cooling system usually can cool the sand from 300C to within +6C of the water supply temperature.
Conclusion While no two metalcasting facilities are the same and
all have different sand systems and requirements, there are many variations of sand reclamation plant available. All that has to be determined is the amount of binder removal required and the level of investment. Modern sand reclamation plants have evolved in such
a way that even the smallest metalcasting facility can be accommodated in terms of floor space required by the plant but also in terms of investment and running costs. Essen- tially, there is a sand reclamation plant to suit every plant’s requirement and budget.
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定影烧熔砂粒。
在回收潮模砂到用于制芯时，车间,热法再生也可以 在机械擦洗前或后使用。
砂冷却和分级
最后一节是关于砂子的冷却和去除灰尘和细屑。经 常被忽略，砂冷却器/分级是同样重要的摩擦单元，因 为除非我们删除所有的烟尘和细颗粒的砂沙，我们将不 会看到点火灼烧减量（LOI）在混频器上的变化损失减 少。
通常情况下，冷却器/分类器将铜砂冷却的铜管式热 交换器的流化床型。的流化空气和所提取分离的空气必 须精细地平衡，从而提供内部的流化室中的负压。这种 压力可以根据需要处理砂的质与量进行调节的罚款金额 在沙滩上。
流化床砂磨料，因此，可以采用铜管作为传热介质， 通常可以使用铜冷却系统冷却旧砂沙内，从30℃到6℃ C的供水温度。
结论
虽然没有两个铸造厂是相同的，都有不同的砂系统和 要求，有很多的旧砂再生装置植物是可利用的变化的， 。所有具有以确定的量的取决于去除粘结剂的量去除需 要的和投资水平。
现代砂再生工厂植物进化出这样一种方式，即使是最 小的可容纳铸造的建筑面积的工厂植物，但在投资和运 行费用方面，。从本质上讲，是一个的砂回收厂，以适 应每个晶圆代工铸造厂的需求和预算。
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Fig. 3. Thermal reclama- tion units remove 100% of all binder and other organic material from the sand.
February 2013
FOUNDRY-PLANET.COM | MODERN CASTING | CHINA FOUNDRY ASSOCIATION | 35
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